Vapor chamber with improved wicking structure

ABSTRACT

The present invention is a vapor chamber including a housing that forms a recess within; at least one wicking structure manufactured from a bundle of wires having capillary voids therebetween that is disposed within the recess; and an amount of working fluid disposed within the recess and in fluid contact with the wicking structure such that fluid may move within the capillary voids in the wicking structures through capillary action.

CLAIM OF PRIORITY

This application claims the benefit of priority of United StatesProvisional Patent Application No. 61/862,625, filed on Aug. 6, 2013.

FIELD OF THE INVENTION

The present invention relates to vapor chambers for use in spreadingheat to be dissipated and, in particular, to a vapor chamber having animproved wicking structure.

BACKGROUND

Semiconductors and other electrical components generate heat as aby-product of their operation. The generated heat can reduce or impedeperformance of the component if not effectively dissipated. Astechnology has advanced, the amount of heat to be dissipated from manyof these components has risen dramatically, while the acceptable cost ofheat dissipating devices has remained constant or dropped. Thereforethere is a need for inexpensive products for dissipating heat that arecapable of dissipating ever greater amounts of heat from an everwidening array of components and devices.

A heat pipe is a simple vapor chamber type heat-exchange device that canquickly transfer heat from one point to another. Heat pipes provide highthermal conductivity with small temperature differences; have a fastthermal response; are small in size and lightweight; come in a largevariety of shapes; require no electrical power supply; are maintenancefree; and reduce the overall system size and costs. The three basiccomponents of a common heat pipe are a housing, a working fluid, and awick or capillary structure. An efficient heat pipe system can beaffected by the heat pipe length, the type of working fluid, the returnwick type, and the number of bends in the heat pipe.

The housing isolates the working fluid from the outside environment. Bynecessity, the housing must be leak-proof, maintain the pressuredifferential across its walls, and enable transfer of heat to take placefrom and into the working fluid. Selection of the housing's fabricationmaterial depends on many factors including compatibility;strength-to-weight ratio; thermal conductivity; ease of fabrication;porosity, etc. The housing acts to transfer heat contained within theworking fluid to the outside environment.

Working fluids are many and varied. The prime consideration is theoperating vapor temperature range. Often, several possible workingfluids may exist within the approximate temperature band. Variouscharacteristics must be examined in order to determine the mostacceptable of these fluids for the application considered such as:thermal stability; compatibility with wick and wall materials; vaporpressure relative to the operating temperature range; latent heat;thermal conductivity; liquid and vapor viscosities; surface tension; andacceptable freezing or pour point. The selection of the working fluidmust also be based on thermodynamic considerations that are concernedwith the various limitations to heat flow occurring within the heatpipe, including viscous, sonic, capillary, entrainment, and nucleateboiling levels. Most heat pipes use water and methanol/alcohol asworking fluid.

The typical wick is a porous structure—made of materials like steel,aluminum, nickel or copper in various pore size ranges—fabricated usingmetal foams, and more particularly felts, the latter being morefrequently used. By varying the pressure on the felt during assembly,various pore sizes can be produced. By incorporating removable metalmandrels, an arterial structure can also be molded in the felt. Theprime purpose of the wick is to generate capillary pressure to transportthe working fluid from the condenser section of the housing to theevaporator section. It must also be able to distribute the liquid aroundthe evaporator section to any area where heat is likely to be receivedby the heat pipe. Often these two functions require wicks of differentforms. The selection of the wick for a heat pipe depends on manyfactors, several of which are closely linked to the properties of theworking fluid.

In operation, one end of the heat pipe attaches to a heat source. As theheat rises to the desired operating temperature, the tube boils theworking fluid and transforms it into a vapor state. As the evaporatingfluid fills the hollow center of the wick, it spreads throughout theheat pipe toward to the cold end. Vapor condensation occurs wherever thetemperature is even slightly below that of the evaporation area. As itcondenses, the vapor releases the heat acquired during evaporation andthe now-condensed working fluid then recedes back to the evaporationsection. In most cases, the application must have gravity working withthe system; that is, the evaporator section (heated) must be lower, withrespect to gravity, than the condenser (cooling) section. When a wickstructure is present in the heat pipe, the fluid recedes therein;otherwise, the fluid recedes gravimetrically. The above thermodynamiccycle continues and helps maintain constant temperatures.

Heat pipes are effective in a number of applications but, unfortunately,traditional heat pipes have significant drawbacks. First, although heatpipes are good at moving heat from one point to another, they are notparticularly effective at spreading heat from multiple inputs on asurface. Second, the wicking structures used in heat pipes are difficultand expensive to manufacture. Finally, although heat pipes may beflattened to increase their surface area, such flattening adds to theoverall cost of manufacture and reduces the effective heat dissipatingcapacity of the heat pipe.

In order to overcome the downsides of traditional heat pipes, othertypes of vapor chambers have been developed. One common type of vaporchamber includes a flat hollow rectangular housing into which isdisposed a wicking structure and a working fluid. The wicking structureis typically a mesh type screen, metal foam, or felts that isspecifically fabricated for this purpose and fills substantially all ofthe inside of the housing. The wicking structure allows the vaporchamber to work against gravity like a wick type heat pipe. Thesewicking structures are again difficult and expensive to manufacture andthe use of these wicking structures limits the versatility of the layoutof the heat dissipating components. Further, the use of traditionalwicking structures requires the vapor chambers to be fairly thick, whichlimits their application.

Therefore, there is a need for a vapor chamber that may be easily andinexpensively manufactured, that has substantial versatility in layoutof wicking structures, that may be made thinner than current vaporchambers or flattened heat pipes, and that are not limited totransferring heat from one point to another.

SUMMARY OF THE INVENTION

The present invention is a vapor chamber.

In its most basic form, the present invention is a vapor chamberincluding a housing that forms a recess within; at least one wickingstructure manufactured from a bundle of wires having capillary voidstherebetween that is disposed within the recess; and an amount ofworking fluid disposed within the recess and in fluid contact with thewicking structure such that fluid may move within the capillary voids inthe wicking structures through capillary action.

The wicking structure preferably includes a plurality of individualwires, preferably between twenty and forty, but less than twenty orgreater than forty may be included. The wicking structures arepreferably made of a non-reactive metal, such as copper. Other materialsout of which the wicking structures may be manufactured includealuminum, carbon fiber and certain plastics, as well as any materialcommonly used in the art. In some embodiments, standard off-the-shelfwire ropes may be used. The individual wires have capillary voidsbetween the wires, within the wicking structure. These capillary voidsmay be three cornered or four cornered depending on the type andorientation of the wires within the bundle. The individual wires withina wicking structure are packed tightly, but not fluid tightly, so thatfluid may still traverse within the capillary voids. There are also“v”-shaped vacancies between the individual wires on the surface of thewicking structures. In practice, the working fluid moves through thesecapillary voids and “v”-shaped vacancies toward the heat source, throughcapillary action. It is preferred that the wicking structures be twistedso that the distance through a capillary void or “v”-shaped vacancy fromone side of the wicking structure to the other is short. More tightlytwisted wire bundles will have a shorter distance than more looselytwisted wire bundles. The wires may also be braided, twisted in pairsand then aligned within the bundle, or twisted in pairs or groups andthen twisted all together, for example. Herein, the term “twisted” mayrefer to any of these possibilities. The wicking structures may also bestraight, or not twisted, but this is less effective in manyapplications, and therefore non-preferred. The capillary action occursregardless of orientation of the vapor chamber and heat source relativeto gravitational forces.

The housing is designed to fit its application, but preferably includesa base and a cover and is small and flat. The recess is formed betweenthe base and the cover. The preferred housing is preferablysubstantially rectangular. Herein, “substantially rectangular” may meanthat the housing is rectangular or that it may be rectangular, but withrounded corners. It is understood that some embodiments may also have ashape other than substantially rectangular. When the cover and base areunited, the preferred housing is 2.5″×5″×0.125″, but may be of smalleror larger dimensions. The housing is preferably made of copper, but maybe made of other materials, such as aluminum, stainless steel, nickel,or refrasil fiber. The working fluid within the recess of the housing ispreferably water, but may be other working fluids, such as acetone,ammonia, methanol, or ethylene-based glycol ether products. The base andcover of the housing are preferably sealed together through welding, butmay also be sealed using epoxy, screws, o-rings, gaskets, or any othermethod commonly used in the art.

In some embodiments, the inside of the housing may be sprayed orotherwise coated with polytetrafluoroethylene (“PTFE,” commonly soldunder the brand name TEFLON) or other non-reactive hydrophobic materialswith similar characteristics to PTFE. With such embodiments, aluminumwire structures, which traditionally have only been usable withnon-water working fluids, may be used with water as the working fluid.This is a significant advantage, as water is dramatically moreeffective, even with the added resistance.

The housing may or may not be vacuum sealed. When the housing is vacuumsealed, the base of the housing may include several separators formaintaining a distance between the cover and base of the housing. Theseparators are small posts extending upward from the floor of the recessin the base to a height so that the cover rests on the top of theseparators. The separators provide mechanical support for the cover sothat it does not buckle into the recess under pressure. When the housingis not vacuum sealed, expansion may be a problem. In these embodiments,at least one, and preferably two, locations may be selected to weld thecover and base together from the outside so as to prevent the cover andbase from expanding away from one another.

The housing preferably includes a fluid input for introducing theworking fluid into the recess. The fluid input is preferably disposedwithin the height of the base, so that the base remains flat. The fluidinput is preferably a small hole within the height of the base with aremovable cap that fits snugly within the hole and prevents leakage ofthe working fluid when in place. The cap may be welded or otherwisepermanently attached, or may be removable to allow the working fluid tobe recharged. Alternatively, any art recognized means of sealing thehole may be utilized. References herein to a “side” of the housingalways refer to the larger, flat sides of the cover or base of thehousing. The height of the housing, which is on all four sides of thehousing, will be referred to as the “height” rather than a “side,” so asto avoid confusion.

In operation, at least one heat source is applied to the outside of thebase or cover of the housing. The wicking structures are preferably wirebundles that act as wicks so that the working fluid moves toward theheat source through the wicking structures by capillary action.

In a preferred embodiment, heat is absorbed on one side of the housing,either the base or the cover depending on where the heat source islocated, and is emitted on the other side of the housing, thereforemoving through the height of the housing. The operation of the heatchamber takes advantage of similar physical properties used with heatpipes, described, for example, in Wallin, Per. “Heat Pipe, selection ofworking fluid.” Project Report MVK160 Heat and Mass Transfer, 7 May2012, hereby incorporated by reference. The traditional heat pipegenerally moves heat from one end of the heat pipe to the other end. Insome embodiments of the vapor chamber of the present invention, heat ismoved similarly to a traditional heat pipe where the heat is movedthrough the length or width of the housing, rather than through theheight of the housing, as described above. Distinctions between thetraditional heat pipe and the vapor chamber of the present inventionwill be evident to one of ordinary skill in the art.

The preferred housing is as described above. It is understood, however,that the housing may also be of the type used traditionally with heatpipes. Heat pipe housings may take any of a variety of forms, such assealed metal tubes. Such a heat pipe housing used in combination withthe wicking structure of the present invention would have significantdifferences from a traditional heat pipe. Where a traditional heat pipetypically includes some sort of porous or sponge-like material as itswick, a heat pipe housing in combination with the wicking structure ofthe present invention would use the wicking structure as its wick. Thewicking structure is unique as a wick because although the individualwire strands are not porous, the bundle of wire strands together isporous, after a fashion, in that it includes the capillary voids, and“v”-shaped vacancies, as discussed above. A heat pipe housing used incombination with a wicking structure of the present invention would alsomove heat via the working fluid in multiple dimensions.

Moreover, a traditional heat pipe typically moves heat via the workingfluid from one end of the heat pipe to the other. A heat pipe housingused in combination with a wicking structure of the present invention,on the other hand, would move heat via the working fluid not only fromone end of the wicking structure to the other, but also from one side ofthe wire bundle to the other through the twists in the wire bundle, asdiscussed above. A traditional tube-like heat pipe housing used incombination with a wicking structure of the present invention wouldpreferably have twisted wire bundle wicking structures aligned aroundthe inner surface of the tube, parallel with one another, and stretchingfrom one end of the heat pipe to the other. In this way, the wickingstructure moves heat via the working fluid from one end of the heat pipeto the other, as in a traditional heat pipe, but also from the insidecavity of the heat pipe to the outer surface of the heat pipe throughthe twists in the wire bundles of the wicking structure.

The wicking structures may be oriented within the recess in any pattern.Patterns of the wicking structures include expanding out from the middlelike a star, in a big swirl, in parallel lines, or in any otherconfiguration that makes sense considering where the heat sources willbe applied to the vapor chamber.

If we consider the side of the vapor chamber on which a heat source isapplied the “hot side” and the other side the “cold side,” liquidworking fluid present in the recess of the housing will move toward thehot side through the capillary voids and “v”-shaped vacancies. On thehot side, the working fluid will evaporate and move back toward the coldside, where it will then condense and be drawn back toward the heat, etcetera. In some embodiments, some sort of additional heat sink or “coldsource” may be applied to the cold side of the housing.

In addition to their utility as described in detail above, mostembodiments of the vapor chamber of the present invention are relativelyeasy and inexpensive to manufacture. It is understood, however, thatsome embodiments may include complex machining details that may increasethe ease and price of manufacture.

These aspects of the present invention are not meant to be exclusive andother features, aspects, and advantages of the present invention will bereadily apparent to those of ordinary skill in the art when read inconjunction with the following description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of a housing of the present invention withthe cover and base separated.

FIG. 1B is a 40:1 magnification of the wicking structures shown in FIG.1A.

FIG. 1C is a cross sectional view of the wicking structures shown inFIG. 1B.

FIG. 1D is a magnification of the shape of a three cornered capillaryvoid.

FIG. 1E is a magnification of the shape of a four cornered capillaryvoid.

FIG. 2A is a top down view of a housing of the present invention.

FIG. 2B is a height view of the housing shown in FIG. 2A.

FIG. 2C is a magnified view of section C-C shown in FIG. 2B.

FIG. 2D is a cross section view of the housing shown in FIG. 2A acrossline A-A.

FIG. 2E is a 4:1 magnification of section B shown in FIG. 2D.

FIG. 2F is a perspective view of a housing of the present invention withthe cover and base separated.

FIG. 2G is a perspective view of a vapor chamber of the presentinvention.

FIGS. 3A-3D are perspective views of various embodiments of a vaporchamber of the present invention with the cover and base separated anddifferent formations of the wicking structures.

FIGS. 4A-4J are various embodiments of the wicking structures.

FIG. 5A is a cutaway top down diagram showing the direction of vaporwithin the vapor chamber.

FIG. 5B is a cutaway height diagram showing the direction of heat andworking fluid within the vapor chamber.

FIG. 6A is a cutaway top down diagram showing a vapor chamber with threeheat sources.

FIG. 6B is a cutaway height diagram of the vapor chamber shown in FIG.6A.

FIG. 7A is a cutaway top down diagram showing a vapor chamber with oneheat source.

FIG. 7B is a cutaway height diagram of the vapor chamber shown in FIG.7A.

FIG. 8A is a cutaway top down diagram showing a vapor chamber with twoheat sources.

FIG. 8B is a cutaway height diagram of the vapor chamber shown in FIG.8A along the short edge.

FIG. 8C is a cutaway height diagram of the vapor chamber shown in FIG.8A along the long edge.

FIG. 9A is a cutaway top down diagram showing a vapor chamber with oneheat source.

FIG. 9B is a cutaway height diagram of the vapor chamber shown in FIG.9A along the short edge.

FIG. 9C is a cutaway height diagram of the vapor chamber shown in FIG.9A along the long edge.

DETAILED DESCRIPTION

Referring first to FIG. 1A, a perspective view of the housing 10 of thevapor chamber of the present invention with cover 12 and base 14separated is provided. Cover 12 mates with rim 13 of base 14. Rim 13provides the height of housing 10 that allows for recess 11 within thehousing 10. Each corner of base 14 includes a hole 18 for affixing thehousing 10 in a specific place or orientation, such as with screws.Wicking structures 20 and separators 16 are disposed within the recess11. The inclusion of separators 16 indicates that this housing 10 willbe under vacuum sealing. In the embodiment shown, wicking structures 20are spreading out from the center in a star-like pattern, but this isjust one of many different patterns in which the wicking structures 10may be oriented, as discussed in more detail below with reference toFIGS. 3A-3D. Although not shown, it is understood that a quantity ofworking fluid 36 will also be disposed within the recess 11 of housing10.

Now referring to FIGS. 1B and 1C, 40:1 magnified views of wickingstructures 20 are provided. FIG. 1B shows a portion of a wickingstructure 20 from the side, along a short length of the thin individualwires 22 within the wicking structure 20. Although not apparent in otherviews, FIG. 1B illustrates that wires 22 are twisted within wickingstructure 20. FIG. 1C shows a cross section of the wicking structure 20including capillary voids 26 between the wires 22 within the wickingstructure 20 and “v”-shaped vacancies 24 between the wires 22 on thesurface of the wicking structure 20. FIG. 1E is a magnification of theshape of a three cornered capillary void 30, such as those includedwithin wicking structure 20 shown in FIG. 1C. FIG. 1D is a magnificationof the shape of a four cornered capillary void 32, shown in FIGS. 4A and4J, for example.

Referring to FIG. 2A, a top down view of a housing 10 is provided. Thepreferred housing 10 is 2.5″ wide and 5″ long. In this view cover 12 andbase 14 are united so that only cover 12, rim 13, within which cover 12sits, and the corners of base 14 with holes 18 are visible. Referring toFIG. 2B, the height 15 of the housing 10 along the long edge is shown.The height 15 is preferably 0.125″, as indicated in FIG. 2E. FIG. 2C isa 2:1 magnification of section C-C shown in FIG. 2B. This view showsfluid input 28. Working fluid 36, which is preferably water, may beintroduced to or removed from the recess 11 through fluid input 28. Asevidenced by the presence of separators 16, the embodiment shown will beunder vacuum. Fluid input 28 therefore must be able to seal the recess11 airtight. One of ordinary skill in the art will recognize that thefluid input 28 shown in FIG. 2C is merely exemplary and that manyvariations thereof may be substituted in other embodiments. FIG. 2D is across sectional view of the housing 10 shown in FIG. 2A across line A-A.In this view, we see cover 12 and base 14 maintaining height 15 byseparators 16. FIG. 2E is a 4:1 magnification of section B shown in FIG.2D. In this view, we see that cover 12 is very thin and sits within rim13 of base 14. We also see that the flat portion of base 14 is also thinlike cover 12. Separators 16 provide mechanical support for the housing10 under vacuum seal so that the cover 12 and base 14 do not buckletoward one another. Recess 11 is shown with wicking structures 20. FIGS.2F and 2G are perspective views of the housing 10 shown in FIGS. 2A-2Ewith the cover 12 and base 14 separated and united, respectively.

Now referring to FIGS. 3A-3D, perspective views of various embodimentsof the vapor chamber of the present invention are provided, with thecover 12 and base 14 separated and with different formations of wickingstructures 20. FIGS. 3A and 3B show a similar pattern to that shown inFIG. 1A, with the wicking structures 20 spreading outward from themiddle of the base 14. As indicated by the presence of separators 16,the housing 10 shown in FIG. 3A will be under vacuum seal. The patternsdepicted in FIGS. 1A, 2F, 3A, and 3B and similar patterns where wickingstructures 20 expand outward in several lines from the middle of recess11 are referred to herein collectively as “star-like patterns.” Thevapor chambers 10 shown in FIGS. 3B-3D do not include separators andtherefore will not be under vacuum seal. In such embodiments, when thecover 12 and base 14 are united, the cover 12 and base 14 may be weldedtogether in one or more locations so as to prevent them from separatingdue to expansion. The sealing of cover 12 and base 14 may also beeffected by epoxy, screws, o-rings, gaskets, or any other methodcommonly used in the art. FIG. 3C shows the wicking structure 20 in aswirled pattern. The pattern depicted in FIG. 3C and similar patternswhere wicking structures 20 expand outward from the middle of recess 11in a round or spiral trajectory are referred to herein collectively as“swirl patterns.” FIG. 3D shows a combination of straight parallelwicking structures 20 and curved wicking structures 20. It is understoodthat wicking structures 20 that are in a straight pattern within therecess 11, such as in FIGS. 3A, 3B, and 3D, preferably still havetwisted individual wires 22 within the wicking structure 20. One ofordinary skill in the art will recognize that these patterns are merelyexemplary and that the wicking structures 20 may be in any pattern. Thepattern is preferably determined considering the application of thevapor chamber and where a heat source 34, as shown in FIGS. 5A and 5B,for example, will be applied.

Now referring to FIGS. 4A-4J, various embodiments of wicking structures20 are provided. FIGS. 4A and 4B show cross sections of wickingstructures 20, with each individual wire 22 visible, as well ascapillary voids 26 and “v”-shaped vacancies 24. In FIG. 4A, all wires 22are the same size and are packed so as to include both three corneredcapillary voids 30 and four cornered capillary voids 32. In FIG. 4B, alarger lead wire 22 is surrounded by smaller wires 22 twisted around it.In this embodiment, all of the capillary voids 26 are three corneredcapillary voids 30. FIG. 4C shows wires 22 in a tight twist formation.FIG. 4D shows wires 22 in a loose twist formation. More tightly twistedwire structures 20, such as that shown in FIG. 4C versus FIG. 4D, haveshorter capillary voids 26 from one side to the other (e.g. from theleft side to the right side). Shorter capillary voids 26 provide ashorter distance for the working fluid 36 to travel. The preferredlength of this distance will vary depending on the application of thevapor chamber. FIG. 4E shows wires 22 in a straight formation. FIG. 4Fshows wires 22 as small twisted ropes twisted together. FIG. 4G showswires 22 as braided ropes twisted together. Each of FIGS. 4C-4G may havewires 22 of all of the same size, as shown in FIG. 4A, or with a largerwire 22 in the middle, as shown in FIG. 4B. FIG. 4H shows wires 22 allof the same size twisted together in a loose twist similar to that shownin FIG. 4D. FIG. 4I shows wires 22 all of the same size in a straightformation similar to that shown in FIG. 4E. FIG. 4J shows wires 22 allof the same size twisted around each other or braided in several sets ofpairs that are brought together to form the wicking structure 20. Thisembodiment is something of a hybrid of twisted and straight as the pairsof wires 22 are twisted around one another, but each pair is essentiallystraight. In other embodiments, the wires 22 may be both twisted aroundone another and twisted as a group within the wicking structure 20.Although the wicking structures 20 may be in a straight formation, asshown in FIGS. 4E and 4I, it is understood that such embodiments arenon-preferred and that it is preferred that the wires 22 within wickingstructure 20 be twisted, such as shown in FIGS. 4C, 4D, 4F, 4G, 4H, and4J. The twisted formations provide a short path from the hot side of ahousing 10 to the cold side. One of ordinary skill in the art willrecognize that there are many ways in which the wires 22 may be arrangedwithin the wicking structures 20, and the embodiments shown in FIGS.4A-4J are merely exemplary.

Now referring to FIGS. 5A and 5B, cutaway top down and height diagrams,respectively, showing the direction of vaporous working fluid 36 withinhousing 10 are provided. The position of heat source 34 shown on top ofhousing 10 in FIG. 5B in dashed lines is also indicated in FIG. 5A indashed lines. Regarding FIG. 5B, it is understood that the surface onwhich heat source 34 is being applied may be either cover 12 or base 14of housing 10. In FIG. 5A, the arrows show the direction of the vaporousworking fluid 36 moving away from heat source 34, the working fluid 36having just absorbed heat from the heat source 34 and evaporated.

In FIG. 5B, the bold straight arrows show the direction of heat and thesmaller squiggly arrows show the direction of the liquid working fluid36. The small squiggly arrows show the liquid working fluid 36 moving inthe “v”-shaped vacancies 24 on the surface of the wicking structure 20between the individual wires 22. It is understood that the working fluid36 is also moving through the capillary voids 26 within the wickingstructure 20, but not visible in this view. In this way, wickingstructure 20 is acting as a wick. The working fluid 36 is drawn towardthe heat source 34 through capillary action. The twisted nature of thewicking structure 20 makes the distance that the working fluid has totravel from the non-heated side of the housing 10 to the side of thehousing 10 on which the heat source 34 is applied very short. The twistformation of the wires 22 within the wicking structure 20 shown in FIGS.5A and 5B is similar to that shown in FIG. 4C. One can see that if theembodiment of the wicking structure 20 shown in FIG. 4D, with a loosertwist formation, were substituted, the distance the working fluid 36would have to travel would be longer.

In practice, the working fluid 36 moves toward the heat source 34, asshown in FIG. 5B, through capillary action through the “v”-shapedvacancies 24 and capillary voids 26 of the wicking structure 20, actingas a wick. As the working fluid 36 approaches the heat source 34, itwill evaporate and move away from the heat source 34, as shown in FIG.5A. It will then condense on the cold side of the housing 10, or theside of the housing 10 on which the heat source 34 is not disposed. Thecondensation releases heat which leaves the housing 10 through the coldside, as shown in FIG. 5B. It is understood that this cycle will occurregardless of orientation of the housing 10, so that it will occur evenwhen the capillary action of the working fluid 36 moving toward the heatsource 34 is going upward or against gravity. Although not shown, insome embodiments, a cold source may be included opposite from the heatsource or in a position to which it is desirable for the vaporousworking fluid 36 to travel to condense.

Referring to FIGS. 6A and 6B, cutaway top down and height diagrams,respectively, of a housing 10 with three heat sources 34 applied to thehousing 10 are provided. Referring to FIGS. 7A and 7B, cutaway top downand height diagrams, respectively, of a housing 10 with one heat source34 applied to the housing 10 are provided. In each of these FIGS. 6A-7B,wicking structures 20 are twisted as is preferred so that the heat ismoved from the hot side of the housing 10 to the cold side. Thesefigures demonstrate that the housing 10 may operate with multiple heatsources 34 applied and with those heat sources 34 applied anywhere onthe housing 10.

In addition to the heat moving from the hot side to the cold side of thehousing 10, the heat may also move toward cooler portions of the vaporchamber along the length of the wicking structures 20. In FIG. 6A, forexample, there is a relatively large space between the middle heatsource 34 and the heat source 34 on the right. This relatively largespace that has no heat applied to it may be relatively cool on bothsides of the housing 10. Therefore, vaporous working fluid 36 movingaway from those heat sources 34, in an action similar to that shown inFIG. 5A, may move through the wicking structures 20 both from one sideof the vapor chamber 20 to the other through the short path created bythe twists, but also along the length of the wicking structure 20 towardthat space to condense on either side of the housing 10 in that space sothat the housing 10 may dispel heat on both sides in that space. Thevaporous working fluid 36 may also move directly through the recess 11to get to cooler space where it will condense.

Referring to FIGS. 8A-8C, cutaway top down and cutaway height diagrams,respectively, of a housing 10 with two heat sources 34 are provided.Referring to FIGS. 9A-9C, cutaway top down and cutaway height diagrams,respectively, of a housing 10 with one heat source 34 are provided.These embodiments of housing 10 are more similar to traditional heatpipes than the embodiments illustrated in and described with referenceto FIGS. 5A-7B. The embodiments shown in FIGS. 8A-9C are similar to heatpipes in that the heat is moved along the length of the wickingstructures 20, akin to a straw, underscoring the discussion regardingFIG. 6A of the relatively large, cool space between two heat sources 34.Especially if the wicking structures 20 shown in FIGS. 8A-9C aretwisted, there will still be heat moving from the hot side of thehousing 10 to the cold side. The embodiments shown in FIGS. 8A-9C,however, lend themselves to wicking structures 20 where the wires 22within the wicking structures 20 are in a straight formation, as shownin FIGS. 4E and 4I, for example. Liquid working fluid 36 will be drawnfrom the left of the housing 10, as shown in FIGS. 8A and 9A through thewicking structures 20, acting as wicks, toward the heat sources 34,where it will evaporate and then move away from the heat sources 34 as agas until it condenses toward the left again and dispels the heat.

Comparing the patterns of the wicking structures 20 in FIGS. 6A-7B withthose of FIGS. 8A-9C is illustrative to show how the vapor chamberapplication may determine the best wicking structure pattern. In FIGS.6A-7B, the wicking structures 20 are twisted so that the main heatmovement is going to be from the side of the housing 10 on which theheat source 34 is applied to the other side. The other side of thehousing 10 therefore needs to be relatively cool so that the heat may bedispelled there. In other words, it will not work well if there isanother heat source on the other side, or if there is a component thatshould not absorb the heat being dispelled from the housing 10 on theother side. In FIGS. 8A-9C, on the other hand, one might imagine that onthe other side of the housing 10 (under the housing 10 shown in FIGS. 8Cand 9C, for example) is a component that should be protected from heator perhaps even another heat source. In such a scenario, as it isundesirable or impossible for the heat to go to the other side of thehousing 10, the heat is instead directed more to the left of the housing10. This would be facilitated by wires 22 in a straight orientationwithin the wicking structures 20 so that the fluid is encouraged to movemore along the length of the wicking structure 20 than between the sidesof the housing 10, as it would be with a twisted wicking structure 20.

Although the present invention has been described in considerable detailwith reference to certain preferred versions thereof, other versionswould be readily apparent to those of ordinary skill in the art.Therefore, the spirit and scope of the description should not be limitedto the description of the preferred versions contained herein.

We claim:
 1. A vapor chamber comprising: a housing; a recess within saidhousing; at least one wicking structure disposed within said recess,wherein: said at least one wicking structure comprises a plurality ofindividual wires; capillary voids are formed between said plurality ofwires within said at least one wicking structure; and v-shaped vacanciesare formed between said plurality of wires on a surface of said at leastone wicking structure; and an amount of working fluid disposed withinsaid recess and in fluid contact with said at least one wickingstructure such that said working fluid is capable of moving through saidcapillary voids and said v-shaped vacancies of said at least one wickingstructure through capillary action.
 2. The vapor chamber as claimed inclaim 1, wherein said capillary voids are shaped as one of a groupconsisting of three cornered and four cornered.
 3. The vapor chamber asclaimed in claim 1, wherein said plurality of individual wires aretwisted.
 4. The vapor chamber as claimed in claim 1, wherein saidhousing comprises a base, a cover and a seal disposed between said baseand said cover and, wherein said base and said cover are removableattached.
 5. The vapor chamber as claimed in claim 1, wherein aninterior of said housing and each of said wires is coated withpolytetrafluoroethylene, and wherein said working fluid is water.
 6. Thevapor chamber as claimed in claim 1, wherein said working fluid iswater.
 7. The vapor chamber as claimed in claim 1, wherein said housingis vacuum sealed and said vapor chamber further comprises at least oneseparator disposed within said recess between said cover and said baseso as to maintain a separation between said cover and said base whilesaid housing is under vacuum.
 8. The vapor chamber as claimed in claim1, wherein at least one location on said housing, said cover and saidbase are affixed together so as to prevent expansion of said cover andsaid base away from one another.
 9. The vapor chamber as claimed inclaim 1, further comprising a fluid input disposed on said housing,wherein said fluid input allows for deposit of said working fluid intosaid recess.
 10. The vapor chamber as claimed in claim 1, wherein saidat least one wicking structure is disposed within said recess in astar-like pattern, expanding outward from a middle of said recess. 11.The vapor chamber as claimed in claim 1, wherein said at least onewicking structure is disposed within said recess in a swirled pattern12. The vapor chamber as claimed in claim 1, wherein said plurality ofindividual wires comprises wires all of the same size.
 13. The vaporchamber as claimed in claim 1, wherein said plurality of individualwires comprises one larger wire surrounded by a plurality of smallerwires.
 14. A vapor chamber comprising: a housing comprising a base, acover, and a recess formed between said base and said cover; and atleast one wicking structure disposed within said recess, wherein: saidat least one wicking structure comprises at least three individualwires; and capillary voids are formed between said wires within said atleast one wicking structures; and an amount of working fluid disposedwithin said recess and in fluid contact with said at least one wickingstructure such that said working fluid is capable of moving through saidcapillary voids through capillary action.
 15. The vapor chamber asclaimed in claim 14, wherein an interior of said housing and each ofsaid at least three wires are coated with polytetrafluoroethylene andwherein said working fluid is water.
 16. The vapor chamber as claimed inclaim 14, wherein said housing is vacuum sealed and said vapor chamberfurther comprises at least one separator disposed within said recessbetween said cover and said base so as to maintain a separation betweensaid cover and said base while said housing is under vacuum.
 17. Thevapor chamber as claimed in claim 14, wherein at least one location onsaid housing, said cover and said base are affixed together so as toprevent expansion of said cover and said base away from one another. 18.A vapor chamber system comprising: a vapor chamber comprising: a housingcomprising a base and a cover; a recess formed between said base andsaid cover when said base and said cover are united; at least onewicking structure disposed within said recess, wherein: said at leastone wicking structure comprises a plurality of individual wires;capillary voids are formed between said wires within said at least onewicking structures; and v-shaped vacancies are formed between said wireson a surface of said at least one wicking structure; and an amount ofworking fluid disposed within said recess and in fluid contact with saidat least one wicking structure such that said working fluid is capableof moving through said capillary voids and said v-shaped vacanciesthrough capillary action; and at least one heat source disposedproximate to one of said base and said cover of said housing of saidvapor structure such that heat from said at least one heat source istransferred through said housing into said working fluid disposed withinsaid housing.
 19. The vapor chamber system as claimed in claim 18,further comprising at least one cold source disposed at a differentposition proximate to one of said base and said cover of said housing ofsaid vapor structure than said at least one heat source, such that heatfrom said working fluid disposed within said housing is transferred fromsaid heat source through said housing into said at least one coldsource.
 20. The vapor chamber system as claimed in claim 19, whereinsaid at least one wicking structure is disposed within said recess ofsaid housing of said vapor chamber such that: a portion of said at leastone wicking structure is proximate to said at least one heat source suchthat said working fluid in fluid contact with said at least one wickingstructure evaporates and moves away from said at least one heat sourcethrough said capillary voids and v-shaped vacancies in said at least onewicking structure; and a portion of said at least one wicking structureis far enough away from said at least one heat source and any other heatsource such that said working fluid that evaporated near said at leastone heat source and moved away from said at least one heat sourcethrough said capillary voids and v-shaped vacancies condenses.